From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from d03relay04.boulder.ibm.com (d03relay04.boulder.ibm.com [9.17.195.106]) by e35.co.us.ibm.com (8.12.10/8.12.9) with ESMTP id j6QIdPSa284034 for ; Tue, 26 Jul 2005 14:39:34 -0400 Received: from d03av02.boulder.ibm.com (d03av02.boulder.ibm.com [9.17.195.168]) by d03relay04.boulder.ibm.com (8.12.10/NCO/VERS6.7) with ESMTP id j6QIdQuN154184 for ; Tue, 26 Jul 2005 12:39:26 -0600 Received: from d03av02.boulder.ibm.com (loopback [127.0.0.1]) by d03av02.boulder.ibm.com (8.12.11/8.13.3) with ESMTP id j6QIdORB017143 for ; Tue, 26 Jul 2005 12:39:24 -0600 Subject: Re: Memory pressure handling with iSCSI From: Badari Pulavarty In-Reply-To: <20050726111110.6b9db241.akpm@osdl.org> References: <1122399331.6433.29.camel@dyn9047017102.beaverton.ibm.com> <20050726111110.6b9db241.akpm@osdl.org> Content-Type: text/plain Date: Tue, 26 Jul 2005 11:39:11 -0700 Message-Id: <1122403152.6433.39.camel@dyn9047017102.beaverton.ibm.com> Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: owner-linux-mm@kvack.org Return-Path: To: Andrew Morton Cc: lkml , linux-mm List-ID: On Tue, 2005-07-26 at 11:11 -0700, Andrew Morton wrote: > Badari Pulavarty wrote: > > > > After KS & OLS discussions about memory pressure, I wanted to re-do > > iSCSI testing with "dd"s to see if we are throttling writes. > > > > I created 50 10-GB ext3 filesystems on iSCSI luns. Test is simple > > 50 dds (one per filesystem). System seems to throttle memory properly > > and making progress. (Machine doesn't respond very well for anything > > else, but my vmstat keeps running - 100% sys time). > > It's important to monitor /proc/meminfo too - the amount of dirty/writeback > pages, etc. > > btw, 100% system time is quite appalling. Are you sure vmstat is telling > the truth? If so, where's it all being spent? > > Well, profile doesn't show any time in "default_idle". So I believe, vmstat is telling the truth. # cat /proc/meminfo MemTotal: 7143628 kB MemFree: 43252 kB Buffers: 16736 kB Cached: 6683348 kB SwapCached: 5336 kB Active: 14460 kB Inactive: 6686928 kB HighTotal: 0 kB HighFree: 0 kB LowTotal: 7143628 kB LowFree: 43252 kB SwapTotal: 1048784 kB SwapFree: 1017920 kB Dirty: 6225664 kB Writeback: 447272 kB Mapped: 10460 kB Slab: 362136 kB CommitLimit: 4620596 kB Committed_AS: 168616 kB PageTables: 2452 kB VmallocTotal: 34359738367 kB VmallocUsed: 9888 kB VmallocChunk: 34359728447 kB HugePages_Total: 0 HugePages_Free: 0 Hugepagesize: 2048 kB # echo 2 > /proc/profile; sleep 5; readprofile - m /usr/src/*12.3/System.map | sort -nr 1634737 total 0.5464 1468569 shrink_zone 390.5769 21203 unlock_page 331.2969 19497 release_pages 46.8678 19061 __wake_up_bit 397.1042 17936 page_referenced 53.3810 10679 lru_add_drain 133.4875 7348 page_waitqueue 76.5417 5877 tg3_poll 2.4007 4650 cond_resched 41.5179 4476 copy_user_generic 15.0201 1973 do_get_write_access 1.2583 1858 __mod_page_state 38.7083 1754 tg3_start_xmit 0.9876 1348 journal_dirty_metadata 2.1063 1250 __find_get_block 2.7902 1224 journal_add_journal_head 2.6379 1082 kmem_cache_free 11.2708 1077 tcp_sendpage 0.3580 1076 tcp_ack 0.1431 1075 __make_request 0.7999 1035 tg3_interrupt_tagged 2.5875 1022 __pagevec_lru_add 4.5625 928 tcp_transmit_skb 0.4677 924 kmem_cache_alloc 14.4375 900 thread_return 3.5294 819 __ext3_get_inode_loc 0.9307 754 established_get_next 2.2440 711 journal_cancel_revoke 1.4335 684 file_send_actor 7.1250 Thanks, Badari -- To unsubscribe, send a message with 'unsubscribe linux-mm' in the body to majordomo@kvack.org. For more info on Linux MM, see: http://www.linux-mm.org/ . Don't email: email@kvack.org